3 Causes of Icing on Heat Pumps


Heat pumps provide heating and cooling all in one system. Like other mechanical devices, they can malfunction. If the heat pump ices up, it may indicate a problem that could be as easy to fix as cleaning up debris around the exterior unit.

Here are three reasons why your heat pump could be icing up. Let’s first look at how refrigerants work and how they could contribute to the problem.


One reason your heat pump might be freezing up is because of its use of refrigerants. While it might sound like a contradiction, a heat pump is basically a refrigeration system. It is made up of a compressor and two coils which are in charge of both cooling and heating a home.

If your system is low on refrigerant, this causes the coils to cool down unevenly. When the coil gets too cold, moisture can condense on the coil, which in the winter turns to ice. While the “do-it-yourself” people might be tempted to tackle this problem themselves, this is one project you need to leave to the professionals. It is illegal for anyone who is not E.P.A. certified to handle refrigerant, so call up your local air conditioning specialist if you suspect this is the cause of your frozen pipes.

Mechanical Causes

When your pipes are frozen, it might be due to mechanical issues with the pump itself. Sometimes debris, old air filters or collapsed duct insulation can block off the airflow around the cooling coil. This will stop any refrigerant from moving through the system, freezing the pipes.

Other Possible Causes

While those are the most common reasons for your pipes to freeze, a broken thermostat, a defective blower belt or dirty coil can also be to blame.

If you suspect that your heating pump has frozen over, contact the professionals at One Hour Air in Largo today!